Hepatitis C: global epidemiology and strategies for control

(-)-Epigallocatechin-3-gallate enhances poly I:C-induced interferon-λ1 production and inhibits hepatitis C virus replication in hepatocytes

AIM

To investigate the effect of (-)-epigallocatechin-3-gallate (EGCG) on polyinosinic-polycytidylic acid (poly I:C)-triggered intracellular innate immunity against hepatitis C virus (HCV) in hepatocytes.

METHODS

A cell culture model of HCV infection was generated by infecting a hepatoma cell line, Huh7, with HCV JFH-1 strain (JFH-1-Huh7). Poly I:C with a high molecular weight and EGCG were used to stimulate the JFH-1-Huh7 cells. Real-time reverse transcription-polymerase chain reaction was used to detect the expression levels of intracellular mRNAs and of intracellular and extracellular HCV RNA. Enzyme-linked immunosorbent assay was used to evaluate the interferon (IFN)-λ1 protein level in the cell culture supernatant. Immunostaining was used to examine HCV core protein expression in Huh7 cells.

RESULTS

Our recent study showed that HCV replication could impair poly I:C-triggered intracellular innate immune responses in hepatocytes. In the current study, we showed that EGCG treatment significantly increased the poly I:C-induced expression of Toll-like receptor 3 (TLR3), retinoic acid-inducible gene I, and IFN-λ1 in JFH-1-Huh7 cells. In addition, supplementation with EGCG increased the poly I:C-mediated antiviral activity in JFH-1-Huh7 cells at the intracellular and extracellular HCV RNA and protein levels. Further investigation of the mechanisms showed that EGCG treatment significantly enhanced the poly I:C-induced expression of IFN-regulatory factor 9 and several antiviral IFN-stimulated genes, including ISG15, ISG56, myxovirus resistance A, and 2'-5'-oligoadenylate synthetase 1, which encode the key antiviral elements in the IFN signaling pathway.

CONCLUSION

Our observations provide experimental evidence that EGCG has the ability to enhance poly I:C-induced intracellular antiviral innate immunity against HCV replication in hepatocytes.

Interaction between Galectin-9/TIM-3 pathway and follicular helper CD4+ T cells contributes to viral persistence in chronic hepatitis C

Both Galectin 9 (Gal-9)/T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) pathway and follicular helper CD4⁺ T (Tfh) cells play important roles in persistent hepatitis C virus (HCV) infection. Thus, we aimed to investigate the regulatory role of interaction between Gal-9/TIM-3 pathway and Tfh cells in chronic hepatitis C. A total of 44 chronic hepatitis C patients and 19 normal controls (NCs) were enrolled in this study. Purified CD4⁺ T cells were cultured by TIM-3 Fc protein, recombinant Gal-9, or IL-21 for 48h. TIM-3 expression, Tfh proportion, and IL-21 production was measured, respectively. The immunomodulatory role of Gal-9/TIM-3 and IL-21 was also investigated in HCV cell culture system in vitro. We found that the percentage corresponding to both TIM-3-positive and CXCR5⁺ICOS⁺ Tfh cells within CD4⁺ T cells, which correlated with HCV RNA replication, was significantly elevated in patients with chronic hepatitis C in comparison with those in NCs. Moreover, blockade of Gal-9/TIM-3 pathway by TIM-3 Fc protein increased Tfh cells proportion, IL-21 mRNA and protein expression within purified CD4⁺ T cells, while activation of Gal-9/TIM-3 signaling by Gal-9 stimulation decreased IL-21 production in both patients with chronic HCV infection and healthy individuals. Meanwhile, high concentrations (100 and 200ng/mL) of IL-21 stimulation also elevated TIM-3 expression on CD4⁺ T cells in chronic hepatitis C. Furthermore, TIM-3 blockage and IL-21 stimulation suppressed mRNA expressions of HCV-induced antiviral proteins (myxovirus resistance A and oligoadenylate synthetase) in Huh7.5 cells without affecting viral replication in HCV cell culture system. The interaction between Gal-9/TIM-3 pathway and Tfh cells contributed to viral persistent in chronic HCV infection, which might be pivotal for development of new therapeutic approaches for chronic hepatitis C.

Chronic Hepatitis C Treatment in Patients with Drug Injection History: Findings of the INTEGRATE Prospective, Observational Study

Introduction

People who inject drugs represent an under-treated chronic hepatitis C virus (HCV)-infected patient population.

Methods

INTEGRATE was a prospective, observational study investigating the effectiveness, safety, and adherence in routine clinical practice to telaprevir in combination with peg-interferon and ribavirin (Peg-IFN/RBV) in patients with history of injecting drug use chronically infected with genotype 1 HCV.

Results

A total of 46 patients were enrolled and included in the intent-to-treat (ITT) population. Among heroin and/or cocaine users (n = 37; 80%), 22% reported use in the past month; 74% (34/46) of patients were on opioid substitution therapy in the pre-treatment phase, and 43% (20/46) discontinued HCV treatment prematurely. Sustained virologic response rate was 54% (25/46) in the ITT population and 74% (25/34) in the per protocol (evaluable-for-effectiveness) population. The main reason for failure in the ITT analysis was loss to follow-up (n = 8; 17%). Adverse events occurred in 91% (42/46) of patients. Mean patient-reported adherence to study drugs was >89% at Week 4, Week 12 and end of treatment.

Conclusion

Despite a high rate of treatment discontinuation (including loss to follow-up), self-reported adherence to treatment was good and virologic cure rates were similar to those reported in large real-world cohorts. Our findings suggest that people with a history of injecting drug use should be considered for treatment of chronic HCV infection, and highlight the need for improvements in patient support to boost retention in care and, in turn, help to prevent reinfection and transmission.

Clinical trial registration

Clinicaltrials.gov identifier, NCT01980290.

Funding

Janssen Pharmaceuticals.

Potential Hepatoprotective Role of Galectin-3 during HCV Infection in End-Stage Renal Disease Patients

Hepatitis C virus infection (HCV), one of the greatest causes of liver disease, is a frequent complication in patients with end-stage renal disease (ESRD) on dialysis. ESRD is defined as decreased glomerular filtration and also accompanied by impaired function of the immune system. Galectin-3 is a β-galactoside-binding lectin, involved in various biological processes including pathogenesis of chronic renal disease. The aim of our study was to estimate disease severity in ESRD HCV⁺ patients and analyze the serum concentrations of IL-1β, IL-4, IL-23, and IL-6; anti-HCV antibodies; and galectin-3. Also, we attempted to determine potential correlation between galectin-3 level and parameters of disease severity ALT and AST. Our results showed decreased levels of ALT and AST (p = 0.00), demonstrating less liver destruction in ESRD HCV⁺ patients in comparison to HCV⁺ patients. Increased levels of IL-6 (p = 0.03) implicate a hepatoprotective role of IL-6 in these patients. Also, level of galectin-3 (p = 0.00) in the serum of ESRD HCV⁺ patients was higher than that of HCV⁺ patients. This alteration was accompanied with negative correlation between galectin-3 and AST and ALT, respectively (p = 0.029; p = 0.033). The presence of increased systemic levels of IL-6 and Gal-3 in ESRD HCV⁺ patients may be an attempt to counteract or limit ongoing proinflammatory processes and to downregulate chronic inflammation, suggesting the new aspects of HCV infection in ESRD patients.

Direct-acting antiviral agents in the therapy of hepatitis C virus-related mixed cryoglobulinaemia: a single-centre experience

BACKGROUND

The efficacy and safety of direct-acting antiviral agents (DAAs) were evaluated in a cohort of prospectively enrolled patients with hepatitis C virus (HCV)-related mixed cryoglobulinaemia (MC), an immune complex-mediated vasculitis of small and medium vessels in which the pathogenetic role of HCV has been clearly established.

METHODS

Twenty-two patients received DAAs. Clinical and laboratory features were recorded at baseline, every 4 weeks until the end of treatment (EoT), and 12 weeks afterwards. Primary efficacy endpoints were (a) sustained virological response 12 weeks after therapy completion (SVR12), (b) regression of symptomatology (clinical response) and (c) cryoglobulin disappearance or cryocrit reduction ≥50% (immunological response). Complete response (CR) was defined as the occurrence of all three primary endpoints; partial response (PR) was defined as the occurrence of SVR12, with or without either immunological or clinical response; and no response was defined as missing the achievement of all three endpoints.

RESULTS

All patients reached SVR12. Compared with basal values, mean cryocrit values were significantly decreased at EoT and SVR12. A significant reduction of alanine transaminase and a parallel increase of complement component C4 levels were also detected. Rheumatoid factor activity was significantly reduced at EoT but not at SVR12. At SVR12, a CR was established in 14 patients (63.7%) and a PR in 8 patients (36.3%). In one patient with small lymphocytic lymphoma, the tumour progressed despite viral clearance. Mild adverse events were recorded in nine patients (40.9%).

CONCLUSIONS

The response rates induced by the use of DAAs in patients with MC were remarkably higher than those previously achieved with pegylated interferon-α/ribavirin, with or without rituximab. A much longer follow-up is desirable to achieve useful information in terms of persistent viral clearance and clinical response.

Profile of Roche's cobas® HCV tests

INTRODUCTION

Molecular assays for detection and accurate quantitation of hepatitis C virus (HCV) RNA have been important for identification and management of the hepatitis C. Furthermore, the HCV genotype should be assessed prior to treatment initiation. Recently, Roche developed the cobas® HCV tests for use on the cobas® 6800/8800 Systems and the cobas® 4800 System and the cobas® HCV genotyping (GT) test for use on the cobas® 4800 System. Areas covered: The analytic and clinical performance of the newly-developed tests is described according to the currently existing literature. Both tests for detection and quantitation of HCV RNA have been shown to be sensitive and linear, and correlate well with established Roche tests used in the routine diagnostic laboratory. The cobas® HCV GT test shows a good performance and is suitable for identification of HCV genotypes 1 to 6 and genotype 1 subtypes a and b in clinical specimens from individuals with chronic HCV infection. Expert commentary: The new tests are effective in screening for hepatitis C infection and in the management of patients with chronic HCV infection ensuring full HCV genotype coverage. They will replace the established Roche tests within the next few years.

Influence of vitamin D on liver fibrosis in chronic hepatitis C: A systematic review and meta-analysis of the pooled clinical trials data

AIM

To investigate the relationship between vitamin D and liver fibrosis in hepatitis C-monoinfected or hepatitis C virus (HCV)-human immunodeficiency virus (HIV) co-infected patients.

METHODS

Pertinent studies were located by a library literature search in PubMed/Embase/Cochrane/Scopus/LILACS by two individual reviewers. Inclusion criteria: (1) studies with patients with HCV or co-infected HCV/HIV; (2) studies with patients ≥ 18 years old; (3) studies that evaluated liver fibrosis stage, only based on liver biopsy; and (4) studies that reported serum or plasma 25(OH)D levels. Studies that included pediatric patients, other etiologies of liver disease, or did not use liver biopsy for fibrosis evaluation, or studies with inadequate data were excluded. Estimated measures of association reported in the literature, as well as corresponding measures of uncertainty, were recorded and corresponding odds ratios with 95%CI were included in a meta-analysis.

RESULTS

The pooled data of this systematic review showed that 9 of the 12 studies correlated advanced liver disease defined as a Metavir value of F3/4 with 25(OH) D level insufficiency. The meta-analysis indicated a significant association across studies.

CONCLUSION

Low vitamin D status is common in chronic Hepatitis C patients and is associated with advanced liver fibrosis.

Hepatitis C treatment: where are we now?

Chronic hepatitis C infection affects millions of people worldwide and confers significant morbidity and mortality. Effective treatment is needed to prevent disease progression and associated complications. Previous treatment options were limited to interferon and ribavirin (RBV) regimens, which gave low cure rates and were associated with unpleasant side effects. The era of direct-acting antiviral (DAA) therapies began with the development of first-generation NS3/4A protease inhibitors in 2011. They vastly improved outcomes for patients, particularly those with genotype 1 infection, the most prevalent genotype globally. Since then, a multitude of DAAs have been licensed for use, and outcomes for patients have improved further, with fewer side effects and cure rates approaching 100%. Recent regimens are interferon-free, and in many cases, RBV-free, and involve a combination of DAA agents. This review summarizes the treatment options currently available and discusses potential barriers that may delay the global eradication of hepatitis C.

Look who's talking-the crosstalk between oxidative stress and autophagy supports exosomal-dependent release of HCV particles

Autophagy is a highly conserved and regulated intracellular lysosomal degradation pathway that is essential for cell survival. Dysregulation has been linked to the development of various human diseases, including neurodegeneration and tumorigenesis, infection, and aging. Besides, many viruses hijack the autophagosomal pathway to support their life cycle. The hepatitis C virus (HCV), a major cause of chronic liver diseases worldwide, has been described to induce autophagy. The autophagosomal pathway can be further activated in response to elevated levels of reactive oxygen species (ROS). HCV impairs the Nrf2/ARE-dependent induction of ROS-detoxifying enzymes by a so far unprecedented mechanism. In line with this, this review aims to discuss the relevance of HCV-dependent elevated ROS levels for the induction of autophagy as a result of the impaired Nrf2 signaling and the described crosstalk between p62 and the Nrf2/Keap1 signaling pathway. Moreover, autophagy is functionally connected to the endocytic pathway as components of the endosomal trafficking are involved in the maturation of autophagosomes. The release of HCV particles is still not fully understood. Recent studies suggest an involvement of exosomes that originate from the endosomal pathway in viral release. In line with this, it is tempting to speculate whether HCV-dependent elevated ROS levels induce autophagy to support exosome-mediated release of viral particles. Based on recent findings, in this review, we will further highlight the impact of HCV-induced autophagy and its interplay with the endosomal pathway as a novel mechanism for the release of HCV particles.